| Question | Answer |
| What are some key differences between ionic and covalent compounds? | * Ionic compounds have high melting and boiling points
*Covalent compounds have low melting and boiling points.
*Ionic compounds conduct electricity when melted
*Covalent compounds are poor electrical conductors. |
| Provide an example of an ionic and covalent compound. | * Example of an ionic compound: RbF
* Example of a covalent compound: CO2 |
| Are ionic compounds usually solids, liquids or gases? | Solids. |
| What state(s) are most common for covalent compounds? | Gases, liquids, or soft solids. |
| Do ionic compounds have high or low melting/boiling points? Explain why. | High melting/boiling points because many have more atoms in each molecule and most have a stronger force between molecules. |
| Do covalent compounds have high or low melting/boiling points? Explain why. | Low melting/boiling points because they have only a few atoms and the forces between molecules is weak. |
| Classify each of the following as a chemical or physical change:
a. Rust forming on a coin?
b. Metal reacting with an acid to produce hydrogen gas:
c. Making popsicles in the freezer:
d. Baking bread
e. Chopping wood
f. Adding sugar to coffee | a. chemical change
b. chemical change
c. physical change
d. chemical change
e. physical change
f. physical change |
| Name these simple ionic compounds:
a. CaCl2
b. K2O
c. Sc2S3
d. Li3P | a. Calcium chloride
b. Potassium oxide
c. Scandium sulphide
d. Lithium phosphide |
| Write formulas for these simple ionic compounds:
a. Beryllium oxide
b. Sodium sulphide
c. Magnesium nitride
d. Zinc chloride | a. BeO
b. Na2S
c. Mg3N2
d. ZNCl2 |
| Name these ionic compounds (containing a multivalent ion)
a. FeO
b. Ni2S3
c. CrCl2
d. TiSe2 | a. Iron (II) oxide
b. Nickel (III) sulphide
c. Chromium (II) chloride)
d.Titanium (IV) selenide |
| Write formulas for these ionic compounds (containing multivalent ions):
a. Cobalt (III) bromide
b. Chromium (II) oxide
c. Niobium (V) fluoride
d. Molybdenum (II) nitride | a. CoBr2
b. CrO
c. NbF5
d. Mo3N2 |
| Name these ionic compounds (containing polyatomic ions):
a. NH3Cl
b. Ca(OH)2
c. K2CO3
d. Mg3(PO4)2 | a. Ammonium chloride
b. Calcium hydroxide
c. Potassium carbonate
d. Magnesium phosphate |
| What is a compound? | A pure substance made of two or more elements that are chemically combined. |
| What is an element? | A pure substance that cannot be broken down into simpler substances (because it is composed of only one kind of atom). |
| What is a covalent compound? | A compound in which two or more atoms combine by sharing electrons. Water (H2O) is an example. |
| What is an ionic substance? | A compound in which oppositely charged ions combine due to mutual attraction. Table salt (NaCl) is an example. |
| What is an ionic lattice? | A repeating pattern of positive and negative ions within an ionic compound. |
| What is a polyatomic ion? | An ion composed of more than one type of atom combined by covalent bonds. |
| What is an exothermic reaction? | A reaction that produces energy usually in the form of light or heat. |
| What is an endothermic reaction? | A reaction that absorbs energy. |
| What is a chemical bond? | A chemical bond is...connections between two or more atoms holding them together. |
| What is a precipitate? | A solid substance that forms in a solution. |
